Surface treatment apparatus and surface treatment method

ABSTRACT

Disclosed is a substrate treatment apparatus. The apparatus includes a support unit that supports and rotates a substrate and a spray unit equipped with one or more nozzles to spray a dual fluid that is a mixture of a cleaning agent and carbon dioxide onto the substrate.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No.10-2019-0151301, filed Nov. 22, 2019, the entire contents of which areherein incorporated by this reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a substrate treatment apparatus and asurface treatment method. More particularly, the present inventionrelates to a substrate treatment apparatus and a substrate treatmentmethod that may be used to manufacture semiconductor devices.

2. Description of the Related Art

Semiconductor devices are manufactured through a number of processesperformed on a semiconductor substrate. The surface of the semiconductorsubstrate is likely to be contaminated with impurities during each ofthe processes. For example, since a silicon wafer, a glass panel, or alarge flat panel for PDP or LCD is contaminated with impurities duringmanufacturing processes, a cleaning process is essentially required toremove the impurities.

Cleaning methods for semiconductor substrates are largely divided into awet chemical method, a dry chemical method, and a vapor phase method.Traditional wafer cleaning methods were mostly wet chemical methodsusing a hydrogen peroxide solution but dry chemical methods or vaporphase methods are now preferably used because disadvantages of the wetchemical methods, including consumption of many chemicals, difficulty indisposing used materials, and incompatibility with advancedmanufacturing processes.

A conventional wet cleaning method for removing impurities from asemiconductor substrate is RCA cleaning which is a set of cleaning stepsthat respectively use ammonia hydrogen peroxide, aqueous fluoric acid,and hydrogen peroxide. On the other hand, a conventional dry cleaningmethod removes impurities on a substrate through evaporation of metalliccontaminants (i.e., metal chlorides) by using chlorine radicalsgenerated through ultraviolet (UV) irradiation. That is, conventionalcleaning techniques to treat the surface of a substrate include a methodof using a large amount of aqueous solution or harmful solution, amethod of activating ozone through ultra-violet radiation (for example,UV-03 cleaning technique), or a method of generating oxygen plasma in avacuum environment.

Among these conventional substrate cleaning methods, an ozone watertreatment method is used to remove specifically a photoresist film on asubstrate. In the process, ozone water is directly sprayed onto asubstrate through nozzles or is supplied to the substrate in the form ofsteam. During the ozone water treatment process, when a wafer (i.e.,substrate) rotates at a low speed, it is difficult to removecontaminants present in a periphery area of the surface of the wafer dueto a pooling phenomenon in which ozone water does not spread well buttends to gather in a center portion of the surface of the wafer.

Specifically, in the case of ozone steam feeding, there is a problem inthat the solubility of ozone is reduced due to an increased temperatureof the steam. Therefore, this method cannot provide high cleaningefficiency. On the other hand, in the case of direct spraying ofcleaning fluid (for example, ozone water), since the cleaning fluid doesnot strongly strike the substrate, this method also cannot provide highcleaning efficiency.

Documents of Related Art Patent Document (Patent Document 1) U.S. Pat.No. 4,029,578 SUMMARY OF THE INVENTION

An objective of the present invention is to provide a substratetreatment apparatus and a substrate treatment method that may increasecleaning efficiency.

One aspect of the present invention provides a substrate treatmentapparatus including: a support unit that supports a substrate androtates the substrate supported thereon; and a spray unit including oneor more nozzles configured to spray a dual fluid that is a mixture of acleaning agent and carbon dioxide onto the substrate.

The spray unit may include: a cleaning agent supply member connected tothe nozzle and configured to supply the cleaning agent to the nozzle;and a carbon dioxide supply member connected to the nozzle andconfigured to supply carbon dioxide to the nozzle.

The apparatus may further include: a rotation speed measuring memberconfigured to measure a rotation speed of a substrate rotating portionof the support unit; and a controller configured to adaptively controlthe number of the nozzles from which the dual fluid is to be sprayedonto the substrate on the basis of the rotation speed measured by therotation speed measuring member.

The controller may perform control such that two or more nozzles of thenozzles are used to spray the dual fluid when the rotation speedmeasured by the rotation speed measuring member is lower than a targetrotation speed.

On the other hand, when the rotation speed measured by the rotationspeed measuring member is equal to or higher than the target rotationspeed, the controller may perform control such that a single nozzle ofthe nozzles is used to spray the dual fluid onto the substrate.

The apparatus may include: a flow velocity measuring member installed inthe spray unit and configured to measure a flow velocity of the dualfluid; and a controller configured to control a pressure of the carbondioxide to be mixed with the cleaning agent on the basis of the flowvelocity measured by the flow velocity measuring member.

The controller may perform a control operation by which the pressure ofthe carbon dioxide to be mixed with the cleaning agent is increased whenthe flow velocity measured by the flow velocity measuring member islower than a target flow velocity.

The controller may perform a control operation by which a notificationindicating that the flow velocity is in a normal state is output whenthe flow velocity measured by the flow velocity measuring member isequal to or higher than a target flow velocity.

The cleaning agent may have a temperature within a range of 1° C. to 10°C.

The cleaning agent may be ozone water.

Another aspect of the present invention provides a substrate treatmentmethod including: rotating a substrate; measuring a rotation speed ofthe substrate; determining the number of nozzles to be used on the basisof the measured rotation speed of the substrate; and spraying a dualfluid composed of a cleaning agent and carbon dioxide onto thesubstrate.

The determining of the number of the nozzles may be performed to selecttwo or more nozzles of the nozzles when the measured rotation speed ofthe substrate is lower than a target rotation speed.

The determining of the number of the nozzles may be performed to selectone nozzle of the nozzles when the measured rotation speed of thesubstrate is higher than a target speed.

The method may further include: measuring a flow velocity of the dualfluid; and controlling a pressure of the carbon dioxide on the basis ofthe measured flow velocity.

The controlling of the pressure of the carbon dioxide may be performedto increase the pressure of the carbon dioxide to be mixed with thecleaning agent when the measured flow velocity is lower than a targetflow velocity.

The controlling of the pressure of the carbon dioxide may be performedto output a notification indicating that the flow velocity is in anormal state when the measured flow velocity is equal to or higher thana target flow velocity.

One embodiment of the present invention provides a substrate treatmentapparatus including: a support unit including a support plate configuredto support a substrate and a rotary motor configured to rotate thesupport plate; and a spray unit including one or more nozzles configuredto spray a dual fluid onto the substrate, the dual fluid being a mixtureof a cleaning agent supplied from a cleaning agent supply member andcarbon dioxide supplied from a carbon dioxide supply member. The nozzleincludes: a first supply portion through which the cleaning agent issupplied from the cleaning fluid supply member; and a second supplyportion through which the carbon dioxide supplied from the carbondioxide supply member. The second supply may be configured to surroundthe first supply unit at an end of the nozzle.

The cleaning agent supply member includes: a cleaning liquid storagetank in which a cleaning agent is stored; a first pipe connecting thecleaning liquid storage tank and the nozzle with each other; a staticpressure valve configured to maintain a pressure of the cleaning agentsupplied to the nozzle; a flow meter configured to measure a flow rateof the cleaning agent supplied from the cleaning agent storage tank tothe nozzle; and a shut-off valve or needle valve configured to block orallow supply of cleaning liquid to the nozzle.

The carbon dioxide supply member includes: a carbon dioxide storage tankin which carbon dioxide is stored, a second pipe connecting the carbondioxide storage tank and the nozzle with each other, and a regulatorinstalled in the second pipe so that the carbon dioxide is discharged ata constant pressure.

The spray unit may include a gripping member that grips the nozzles anda turning member that turns the gripping member to be shuttled between astorage position and a substrate position.

According to the present invention, the substrate treatment apparatusincludes the spray unit that sprays a dual fluid that is a mixture of acleaning agent and carbon dioxide onto a substrate. As the concentrationof ozone is increased, the performance of cleaning the substrate isimproved. The concentration of ozone may be maintained high until thedual fluid comes into contact with the substrate after being sprayedfrom the spray unit. The substrate treatment apparatus according to oneembodiment of the present invention may increase a cleaning efficiencycompared to conventional substrate treatment apparatuses.

The substrate treatment apparatus according to one embodiment of thepresent invention may spray a dual fuel toward a substrate at a highvelocity, thereby increasing the force of hitting the substrate toincrease a cleaning efficiency. The substrate treatment apparatusaccording to one embodiment of the present invention may prevent theconcentration of zone from being reduced by using carbon dioxide,thereby increasing a cleaning efficiency while using a chemical cleaningmethod. That is, the substrate treatment apparatus according to oneembodiment of the present invention may significantly improve thecleaning efficiency by using both physical and chemical methods comparedto conventional substrate treatment apparatuses.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objectives, features, and other advantages of thepresent invention will be more clearly understood from the followingdetailed description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a configuration view illustrating a substrate treatmentapparatus according to one embodiment of the present invention;

FIG. 2 is a configuration view illustrating a spray unit;

FIG. 3 is a view illustrating an internal structure of a nozzle includedin the spray unit of FIG. 2;

FIG. 4 is a view illustrating the spray unit viewed from the direction“U” of FIG. 3;

FIG. 5 is a diagram illustrating a spray unit equipped with multiplenozzles;

FIG. 6 is a graph illustrating solubility of ozone to water depending ontemperature;

FIG. 7 is a diagram illustrating a state in which a dual fluid strikes aforeign particle on a substrate in a substrate treatment apparatus;

FIG. 8 is a flowchart illustrating a substrate treatment methodaccording to a first embodiment of the present invention; and

FIG. 9 is a flowchart illustrating a substrate treatment apparatusaccording to a second embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinbelow, exemplary embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings suchthat the invention may be easily practiced by those ordinarily skilledin the art to which the present invention pertains. The presentinvention may be embodied in various forms and should not be construedas being limited to the exemplary embodiments disclosed herein.

A description of elements that are not related to the invention will beomitted to clarify the invention, and identical or similar elements aredenoted by identical or similar reference characters throughout thedrawings and the detailed description below.

In various embodiments, components having the same configuration will bedenoted by the same reference numerals, and only a representativeembodiment will be described. For the other exemplary embodiments, onlycomponents that differ from those of the representative embodiment willnot be described.

When an element is described as being “connected to”, “combined with”,or “coupled to” another element, it should be understood that theelement may be connected to, combined with, or coupled to anotherelement directly or with another element interposing therebetween.

It will be further understood that the terms “comprises”, “comprising”,“includes”, and/or “including,” when used herein, specify the presenceof stated features, integers, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, integers, steps, operations, elements, components,and/or groups thereof.

In addition, unless otherwise defined, all terms including technical andscientific terms used herein have the same meaning as commonlyunderstood by those who are ordinarily skilled in the art to which thisinvention belongs. It will be further understood that terms, such asthose defined in commonly used dictionaries, should be interpreted ashaving a meaning that is consistent with their meaning in the context ofthe relevant art and the present disclosure, and will not be interpretedin an idealized or overly formal sense unless expressly so definedherein.

Referring to FIGS. 1 to 4, according to one embodiment of the presentinvention, a substrate treatment apparatus 100 includes a support unit110 and a spray unit 120.

The support unit 110 supports a substrate W and rotates the substrate Wsupported thereon. The support unit 110 includes, for example, a supportplate 111 and a rotary motor 112.

The support plates 111 supports the substrate W. The support plate 111is larger in size than the substrate S. When the substrate is a circularwafer, the support plate 111 may be a circular plate having a largerdiameter than the wafer.

The rotary motor 112 is positioned below the support plate 111. Therotary motor 112 rotates the support plate 111.

When the substrate W is seated on the support plate 111 and then thesupport plate 111 is rotated, the substrate W on the support plate 111is also rotated. In this state, when a chemical solution is ejected to acenter portion of the substrate W, the chemical solution spreads to theedge of the substrate W due to centrifugal force.

The spray unit 120 includes one or more nozzles 121 for spraying a dualfluid to the substrate W. Herein, the dual fluid refers to a fluidmixture of cleaning agent and carbon dioxide. While the spray unit 120sprays the dual fluid to the substrate, the substrate W may beoptionally irradiated with ultraviolet radiation (see FIG. 7).

The substrate treatment apparatus 100 according to one embodiment of thepresent invention includes a spray unit 120 equipped with one nozzle 121and a spray unit 120 equipped with multiple nozzles 121. Alternatively,according to one embodiment of the present invention, the substratetreatment apparatus 100 may include a spray unit 120 equipped withmultiple nozzles 121 that may be selectively or collectively used.

The spray unit 120 includes, for example, one or more nozzles 121, acleaning agent supply member 123, and a carbon dioxide supply member122.

The nozzle 121 is configured to spray the cleaning agent and the carbondioxide toward the substrate W. Referring to FIGS. 3 and 4, the nozzle121 includes a first supply portion 121 a through which a cleaning agentis introduced and a second supply portion 121 b through which carbondioxide is introduced.

At an end of the nozzle 121, the first supply portion 121 a issurrounded by a portion of the second supply portion 121 b. Carbondioxide is sprayed at around a jet of the cleaning agent. Therefore, thecarbon dioxide is mixed with the cleaning agent while the carbon dioxideis sprayed toward the substrate W, and the speed of the cleaning agentsprayed toward the substrate W is increased due to a high speed of thecarbon dioxide sprayed toward the substrate W.

The cleaning agent supply member 123 is connected to the nozzle 121. Thecleaning agent supply member 123 is configured to feed the cleaningagent to the nozzle 121. The cleaning agent used to clean the substrateW is, for example, ozone water. When a mixture of ozone water and carbondioxide is sprayed onto the substrate W, the rate of dissociation ofozone on the substrate W is reduced due to the presence of the carbondioxide.

When carbon dioxide and ozone water (cleaning agent) are mixed,reactions indicated by Reaction Formulas below occur.

C0₂+H₂0↔HC0₃+H⁺

HCO₃—↔CO₃ ²⁻+H⁺

CO₃ ²⁻+OH.↔CO₃—.+OH⁻

CO₃—.+OH.↔C0₂+H0₂—

0₃+HO₂—↔OH.+0₂—.+0₂

As can be seen from the above reaction formulas, carbon dioxide (CO₂)and ozone water (i.e., cleaning agent) react to produce subcarbonate(HCO₃), and then the subcarbonate is converted into carbonate (CO₃ ²⁻).This carbonate prevents the dissociation of ozone (O₃).

More specifically, the cleaning agent supply member 123 includes acleaning agent storage tank 123 a, a first pipe 123 f, a static pressurevalve 123 b, a flow meter 123 c, a shut-off valve 123 d, and a needlevalve 123 e.

The cleaning agent storage tank 123 a stores the cleaning agent. Thefirst pipe 123 f connects the cleaning agent storage tank 123 a to thenozzle 121.

The static pressure valve 123 b maintains the pressure of the pipe whenthe cleaning agent is supplied to the nozzle 121. The flow meter 123 cmeasures the flow rate of the cleaning agent supplied to the nozzle 121from the cleaning agent storage tank 123 a.

The shut-off valve 123 d blocks and allows the flow of the cleaningagent toward the nozzle. The needle valve 123 e is a valve operated byan external force. A user may manually block or allow the flow of thecleaning agent toward the nozzle.

The cleaning agent supply member 123 is configured to stably feed thecleaning agent to the nozzle 121.

The carbon dioxide supply member 122 is connected to the nozzle 121 andsupplies carbon dioxide to the nozzle 121. The carbon dioxide supplymember 122 includes a carbon dioxide storage tank 122 a, a second pipe122 c, and a regulator 122 b.

The carbon dioxide storage tank 122 a stores carbon dioxide. The secondpipe 122 c connects the carbon dioxide storage tank 122 a to the nozzle121. The regulator 122 b is configured to discharge carbon dioxide fromthe carbon dioxide storage tank 122 a at a constant pressure.

The carbon dioxide supply member 122 is configured to stably supplycarbon dioxide to the nozzle 121.

On the other hand, when the spray unit 120 includes multiple nozzles121, the carbon dioxide supply member 122 includes multiple regulators122 b respectively connected to the multiple nozzles 121. The multipleregulators 122 b regulate the flow velocity of a dual fluid sprayed fromthe multiple nozzles 121, respectively.

The spray unit 120 further includes a gripping member 124 and a rotatingmember 125 (see FIG. 5). The gripping member 124 grips the multiplenozzles 121. The rotating member 125 rotates the gripping member 124.

When one of the nozzles 121 is not used, the rotating member 125 movesthe gripping member 124 to a storage position (not shown). On the otherhand, when one of the nozzles 121 is used, the rotating member 125rotates the gripping member 124 so as to be positioned above thesubstrate W. However, the spray unit 120 includes the gripping member124 and the rotating member 125 in the case where the spray unit 120 isequipped a single nozzle 121 as well as in the case where the spray unit120 is equipped with multiple nozzles 121.

A proper gap H (see FIG. 1) between the nozzle 121 and the substrate Wis preferably maintained during the process of spraying the dual fluidto the substrate W. When the gap H between the nozzle 121 and thesubstrate W is excessively large, the jet speed of the dual fluidsprayed from the nozzle is lower than a required jet speed. In thiscase, it is difficult for the sprayed dual fluid to strongly hit thesubstrate W, reducing efficiency of removal of foreign particles on thesubstrate W.

Conversely, when the gap H between the nozzle 121 and the substrate W issmall, the jet speed of the dual fluid sprayed from the nozzle does notdecrease significantly until the dual fluid reaches the substrate W.Therefore, the dual fluid may strongly hit the substrate W when reachingthe substrate W, thereby reliably removing foreign particles T on thesubstrate W.

Here, the gap H between the nozzle 121 and the substrate W variesdepending on the design of the substrate treatment apparatus 100. Thatis, the gap H is not limited to a specific value.

Although not illustrated in the drawings, the substrate treatmentapparatus 100 according to one embodiment of the present inventionincludes a chemical recovery unit.

The chemical recovery unit is positioned near the support unit 110 andcollects a fluid escaping from the support unit 110. In more detail, thechemical recovery unit is installed to surround the entire circumferenceof the support unit 110 and recovers a fluid scattering from the supportunit 110.

The chemical recovery unit may separately recover different fluids usedduring a surface treatment process. The chemical recovery unit has aplurality of inlets 131 through which various fluids may be introducedinto the chemical recovery unit. The inlets 131 are arranged in avertical direction. That is, the inlets 131 are positioned at differentheights.

In a process of treating the substrate W, each of the various fluids maybe separately introduced into and stored in a corresponding compartmentof multiple compartments in the chemical recovery unit. The fluidsintroduced into the chemical recovery unit through the respective inlets131 are separately transferred to an external chemical regeneration unit(not illustrated) through respective recovery pipes, are regenerated bythe chemical regeneration unit, and are reused. The chemicalregeneration unit is an apparatus for regenerating a fluid so as to bereused. For example, the chemical regeneration unit adjusts theconcentration and temperature of the recovered fluid and then filtersthe resulting fluid.

In the process of treating the substrate W, contaminants such asparticles generated during the treatment process may be introduced intothe chemical recovery unit or fume may be generated from the remainingfluid in the chemical recovery unit. These contaminants are removed bythe chemical regeneration unit. Therefore, it is possible to prevent thesubstrate from being contaminated in the subsequent substrate treatmentprocess when the recycled fluid is reused.

The chemical recovery unit may be a typical one that is usually used forconventional substrate treatment apparatuses. Therefore, a detaileddescription of the chemical recovery unit will be omitted.

The substrate treatment apparatus 100 according to one embodiment of thepresent invention further includes a rotation speed measuring member 130and a controller 150. In an example embodiment, the rotation speedmeasuring member 130 may include a tachometer.

The rotation speed measuring member 130 measures the rotation speed of asubstrate rotation portion of the support unit 110. In more detail, therotation speed measuring member 130 is connected to a rotary motor 112of the support unit 110.

The rotation speed measuring member 130 receives information on therotation speed from the rotary motor 112 and indirectly detects therotation speed of the substrate W. Alternatively, the rotation speedmeasuring member 130 is an RPM sensor that measures the rotation speedof the support plate 111.

The controller 150 controls the number of nozzles 121 to be used on thebasis of the rotation speed measured by the rotation speed measuringmember 130.

In more detail, when the rotation speed measured by the rotation speedmeasuring member 130 is lower than a target rotation speed, thecontroller 150 performs a control operation such that the dual fluid issprayed to the substrate W from two or more nozzles 121.

Unlike this case, when the dual fluid is sprayed to a center portion ofthe substrate W from only one nozzle 121 in a state in which thesubstrate W is rotated at a low speed, it is not possible to obtain acentrifugal force sufficient to spread the dual fluid across the entiresurface of the substrate W. Accordingly, a pooling phenomenon in whichthe dual fluid does not evenly spread over the entire area of thesurface but gathers in a limited area occurs.

However, in the case of using the substrate treatment apparatus 100according to one embodiment of the present invention, since the dualfluid is sprayed from the multiple nozzles 121, although the substrate Wis rotated at a low speed, the entire area of the surface including thecenter portion and the edge portion may be sprayed with a sufficientamount of cleaning agent.

In more detail, when the rotation speed measured by the rotation speedmeasuring member 130 is higher than the target rotation speed, thecontroller 150 performs a control operation such that the dual fluid issprayed to the substrate W from only one nozzle 121. When the substrateW is rotated at a high speed, even though a cleaning agent is sprayedonly to a center portion of the surface of the substrate W, the cleaningagent rapidly spreads to cover the entire area of the surface of thesubstrate W.

In the case in which the cleaning agent is sprayed to the substrate Wfrom only one nozzle 121, the consumption of the cleaning agent isreduced, resulting in reduction in the cost surface treatment of thesubstrate W.

The substrate treatment apparatus 100 according to one embodiment of thepresent invention further includes a flow velocity measuring member 140and a controller 150.

The flow velocity measuring member 140 is installed in the spray unit120. In more detail, the flow velocity measuring member 140 is installedon the second pipe 122 c included in the carbon dioxide supply member122. The flow velocity measuring member 140 measures the flow velocityof the dual fluid.

The controller 150 controls the pressure of carbon dioxide mixed withthe cleaning agent on the basis of the flow velocity of the dual fluid,which is measured by the flow velocity measuring member 140.

The controller may perform a control operation such that the pressure ofthe carbon dioxide to be mixed with the cleaning agent is increased whenthe flow velocity measured by the flow velocity measuring member 140 islower than a target flow velocity. Since the cleaning agent and thecarbon dioxide are simultaneously sprayed, the jet speed of the cleaningagent is proportional to the pressure of the carbon dioxide supplied tothe nozzle 121.

Thereby, when the pressure of the carbon dioxide supplied to the nozzleis increased, the jet speed of the dual fluid increases so that the dualfluid may strongly hit the surface W when coming into contact with thesubstrate W. The dual fuel sprayed toward the substrate W at a highvelocity strongly strikes foreign particles on the substrate W.Therefore, the foreign particles on the substrate W may be easilyremoved from the substrate W.

In addition, the substrate treatment apparatus 100 according to oneembodiment of the present invention, may supply a sufficient amount(thickness) of cleaning agent to clean the substrate W compared toconventional substrate treatment apparatuses that use steam forcleaning.

On the other hand, the controller may perform a control operation suchthat a notification indicating that the flow velocity is in a normalstate is output when the flow velocity measured by the flow velocitymeasuring member is equal to or higher than the target flow velocity.The state in which the measured flow velocity is equal to or higher thanthe target flow velocity means that the dual fluid is sprayedsufficiently fast to remove the foreign particles by the spray unit 120.

The controller 150 may perform a control operation such that an LED lampinstalled outside the substrate treatment apparatus flashes or such thata message of “Normal State” is displayed on a display screen to notifythe user of the operating state of the surface treatment apparatus. Thisnotification event allows the user to confirm that the substratetreatment apparatus 100 is operating normally.

On the other hand, in the case where a low-pressure low-velocity dualfluid is sprayed onto the substrate W by the spray unit 120, the dualfluid cannot strike the substrate W with a sufficient force so that thesubstrate W cannot be reliably cleaned. However, since the substratetreatment apparatus 100 according to one embodiment of the presentinvention is equipped with the flow velocity measuring member 140 andthe controller 150, the dual fluid may strike the surface of thesubstrate W with a sufficiently strong force to completely removeforeign particles on the substrate.

The substrate treatment apparatus 100 according to one embodiment of thepresent invention may spray a dual fuel toward a substrate at a highvelocity, thereby increasing the force of hitting the substrate toincrease a cleaning efficiency.

In addition, the substrate treatment apparatus 100 according to oneembodiment of the present invention may prevent the concentration ofozone from being reduced by using carbon dioxide, thereby increasing acleaning efficiency while using a chemical cleaning method. That is, thesubstrate treatment apparatus 100 according to one embodiment of thepresent invention may significantly improve the cleaning efficiency byusing both physical and chemical methods compared to conventionalsubstrate treatment apparatuses.

The temperature of the cleaning agent used in the substrate treatmentapparatus 100 according to one embodiment of the present inventionpreferably is preferably in a range of 1° to 10°. The substratetreatment apparatus 100 according to one embodiment of the presentinvention simply mixes a cleaning agent and carbon dioxide and thensprays the resulting mixture to a substrate W as it is unlikeconventional substrate treatment apparatuses that typically heat acleaning agent before spraying the cleaning agent to a substrate W.Therefore, the substrate treatment apparatus 100 according to oneembodiment of the present invention may spray a cleaning agent onto asubstrate W while maintaining the cleaning agent at a low temperature.

Referring to FIG. 6, A is ozone water having an ozone concentration of1% and B is ozone water having an ozone concentration of 2%. As shown inthe graph, the lower the temperature of the ozone water, the greater thesolubility of the ozone water.

The substrate treatment apparatus 100 according to one embodiment of thepresent invention sprays a dual fluid that is a mixture of alow-temperature cleaning agent and carbon dioxide onto the substrate W.Therefore, the dual fluid maintains a high ozone concentration untilreaching the surface of the substrate W, thereby efficiently removingforeign particles from the surface of the substrate W. That is, thesubstrate treatment apparatus 100 according to one embodiment of thepresent invention exhibits significantly higher cleaning performancethan conventional substrate treatment apparatuses.

As described above, the substrate treatment apparatus 100 according toone embodiment of the present invention includes the spray unit 120 thatsprays a mixture of a cleaning agent and carbon dioxide to a substrateW. The cleaning performance improves with increasing ozone concentrationin the dual fluid. The concentration of ozone may be maintained highuntil the dual fluid comes into contact with the substrate W after beingsprayed from the spray unit 120. The substrate treatment apparatusaccording to one embodiment of the present invention may increase acleaning efficiency compared to conventional substrate treatmentapparatuses.

The substrate treatment apparatus 100 according to one embodiment of thepresent invention may spray a dual fuel toward a substrate at a highvelocity, thereby increasing the force of hitting the substrate toincrease a cleaning efficiency. In addition, the substrate treatmentapparatus 100 according to one embodiment of the present invention mayprevent the concentration of ozone from being reduced by using carbondioxide, thereby increasing a cleaning efficiency while using a chemicalcleaning method. That is, the substrate treatment apparatus 100according to one embodiment of the present invention may significantlyimprove the cleaning efficiency by using both physical and chemicalmethods compared to conventional substrate treatment apparatuses.

Hereinafter, a substrate treatment method using the substrate treatmentapparatus 100 described above will be described.

Referring to FIG. 8, a substrate treatment method S100 according to afirst embodiment of the present invention includes a substrate rotationstep S110, a rotation speed measurement step S120, a nozzle countdetermination step S130, and a dual fluid spraying step S150.

The substrate rotation step S110 is a step of rotating a substrate. Whenthe support plate of the support unit is rotated, the substratesupported on the support plate is accordingly rotated.

The rotation speed measurement step S120 is a step of measuring therotation speed of the substrate.

The nozzle count determination step S130 is a step of setting the numberof nozzles to be used on the basis of the measured rotation speed of thesubstrate. The nozzle count determination step S130 includes a sub-stepof selecting two or more nozzles of the nozzles when the measuredrotation speed is lower than a target rotation speed. The nozzle countdetermination step S130 includes a sub-step of selecting one nozzle whenthe measured rotation speed is higher than the target rotation speed.

The dual fluid spraying step S150 is a step of spraying a dual fluidwhich is a mixture of cleaning agent and carbon dioxide onto thesubstrate.

Referring to FIG. 9, a substrate treatment method S200 according to asecond embodiment of the present invention additionally includes a flowvelocity measurement step S160 and a pressure control step S170 comparedto the substrate treatment apparatus 100.

The flow velocity measurement step S160 is a step of measuring the flowvelocity of the dual fluid.

The pressure control step S170 is a step of controlling the pressure ofcarbon dioxide supplied to the nozzle on the basis of the measured flowvelocity.

The pressure control step S170 includes a pressure increasing step S180of increasing the pressure of carbon dioxide mixed with the cleaningagent when the measured flow velocity is lower than a target flowvelocity. Conversely, the pressure control step S190 includes anotification step S190 of outputting a notification indicating that theflow velocity is in a normal state when the measured flow velocity isequal to or higher than the target flow velocity.

The effects and detailed description of the other steps included in thesubstrate treatment method S200 according to the second embodiment ofthe present invention will be omitted because they are described abovein connection with the substrate treatment apparatus.

Although various embodiments of the present invention have beendescribed above, the drawings and detailed description of the presentinvention are intended to illustrate the present invention and are notintended to limit the scope of the present invention. Therefore, thoseskilled in the art will appreciate that various modifications andequivalents thereto are possible. Accordingly, the true technicalprotection scope of the present invention should be determined by thetechnical idea defined in the appended claims.

What is claimed is:
 1. A substrate treatment apparatus comprising: asupport unit configured to support a substrate and rotate the substratesupported thereon; and a spray unit including a plurality of nozzles forspraying a dual fluid composed of a cleaning agent and carbon dioxideonto the substrate.
 2. The apparatus according to claim 1, wherein thespray unit comprises: a cleaning agent supply member connected to theplurality of nozzles and configured to supply the cleaning agent to theplurality of nozzles; and a carbon dioxide supply member connected tothe plurality of nozzles and configured to supply the carbon dioxide tothe plurality of nozzles.
 3. The apparatus according to claim 1, furthercomprising: a rotation speed measuring member configured to measure arotation speed of a substrate rotating portion of the support unit; anda controller configured to adaptively control the number of nozzles tobe used among the plurality of nozzles on the basis of the rotationspeed measured by the rotation speed measuring member.
 4. The apparatusaccording to claim 3, wherein the controller is configured to set, inresponse to when the rotation speed measured by the rotation speedmeasuring member is lower than a target rotation speed, the number ofnozzles to be used to be two or greater.
 5. The apparatus according toclaim 3, wherein the controller is configured to set, in response towhen the rotation speed measured by the rotation speed measuring memberis equal to or higher than a target rotation speed, to be one.
 6. Theapparatus according to claim 1, further comprising: a flow meterinstalled in the spray unit and configured to measure a flow velocity ofthe dual fluid; and a controller configured to control a pressure of thecarbon dioxide to be mixed with the cleaning agent on the basis of theflow velocity measured by the flow meter.
 7. The apparatus according toclaim 6, wherein the controller is configured to cause, in response tothe flow velocity measured by the flow meter is lower than a target flowvelocity, the pressure of the carbon dioxide to be mixed with thecleaning agent to increase.
 8. The apparatus according to claim 6,wherein the controller is configured to provide, in response to when theflow velocity measured by the flow meter is equal to or higher than atarget flow velocity, a notification indicating that the flow velocityis in a normal state.
 9. The apparatus according to claim 1, wherein atemperature of the cleaning agent is in a range of 1° C. to 10° C. 10.The apparatus according to claim 1, wherein the cleaning agent is ozonewater.
 11. A method of treating a substrate, the method comprising:rotating a substrate; measuring a rotation speed of the substrate;determining the number of nozzles to be used among a plurality ofnozzles on the basis of the measured substrate rotation speed; andspraying a dual fluid from the nozzles to be used onto the substrate,the dual fluid being a mixture of a cleaning agent and carbon dioxide.12. The method according to claim 11, wherein the determining of thenumber of nozzles to be used includes: selecting, in response to whenthe measured rotation speed of the substrate is lower than a targetrotation speed, the nozzles to be used among the plurality of nozzles.13. The method according to claim 11, wherein the determining of thenumber of nozzles to be used includes: selecting, in response to whenthe measured rotation speed of the substrate is higher than a targetrotation speed, one nozzle among the plurality of nozzles.
 14. Themethod according to claim 11, further comprising: measuring a flowvelocity of the dual fluid; and controlling a pressure of the carbondioxide supplied to the nozzles to be used, on the basis of the measuredflow velocity.
 15. The method according to claim 14, wherein thecontrolling of the pressure includes: increasing, in response to whenthe measured flow velocity is lower than a target flow velocity, thepressure of the carbon dioxide to be mixed with the cleaning agent. 16.The method according to claim 14, wherein the controlling of thepressure includes providing, in response to when the measured flowvelocity is equal to or higher than a target flow velocity, anotification indicating that the flow velocity is in a normal state. 17.A substrate treatment apparatus comprising: a support unit including asupport plate configured to support a substrate and a rotary motorconfigured to rotate the support plate; and a spray unit including aplurality of nozzles configured to spray a dual fluid onto thesubstrate, the dual fluid being a mixture of a cleaning agent suppliedby a cleaning agent supply member and carbon dioxide supplied by acarbon dioxide supply member onto a substrate, wherein each of theplurality of nozzles includes a first supply portion through which thecleaning agent is supplied by the cleaning agent supply member and asecond supply portion through which the carbon dioxide is supplied bythe carbon dioxide supply member, and wherein the second supply portionis configured to surround the first supply portion at an end portion ofeach of the plurality of nozzle.
 18. The apparatus according to claim17, wherein the cleaning agent supply member comprises: a cleaning agentstorage tank that stores a cleaning agent; a first pipe that connectsthe cleaning agent storage tank and each of the plurality of nozzles toeach other; a static pressure valve configured to maintain a pressure ofthe cleaning agent supplied to the plurality of nozzles; a flow meterconfigured to measure a flow rate of the cleaning agent supplied fromthe cleaning agent storage tank to the plurality of nozzles; and ashut-off valve or needle valve configured to block or allow supply ofthe cleaning agent to the plurality of nozzles.
 19. The apparatusaccording to claim 17, wherein the carbon dioxide supply membercomprises: a carbon dioxide storage tank that stores carbon dioxide; asecond pipe that connects the carbon dioxide storage tank and theplurality of nozzles to each other; and a regulator installed in thesecond pipe and configured to cause the carbon dioxide to be dischargedat a constant pressure from the plurality of nozzles.
 20. The apparatusof claim 17, wherein the spray unit includes a gripping memberconfigured to grip the plurality of nozzles and a turning memberconfigured to turn the gripping member to be shuttled between a storageposition and a substrate position.